Q&A

Q&A with Thomas LaRock: The Top 5 Common SQL Server Problems (and How To Fix Them)

A Microsoft data platform MVP on the state of SQL Server today -- how it's evolved in Microsoft's Azure-first word, the best features to emerge in recent years and troubleshooting gotchas.

• By Gladys Rama
• 09/14/2021

With over two decades of IT experience, Microsoft data platform MVP Thomas LaRock has seen nearly every SQL Server troubleshooting nightmare under the sun. In an upcoming session called "The Top 5 Common Problems with SQL Server (and How to Fix Them)," part of November's Live! 360 conference in Orlando, Fla., he'll share some of the most likely -- and some of the least-obvious -- culprits that are bogging down databases and hurting their performance.

LaRock spoke with us recently to answer questions about the state of SQL Server today -- how it's evolved in Microsoft's Azure-first word, the best features to emerge in recent years and troubleshooting gotchas.

Redmond: How has Microsoft's effort to Azure-ify everything affected SQL Server's evolution in recent years? Has this posed any problems for DBAs and IT shops?
LaRock: I believe Azure has been the best thing for SQL Server and the data platform as a whole. We used to wait three to five years for new versions of SQL Server! Today, Microsoft pushes new features to Azure first, using it as a test sandbox, before the features make it to the Earthed version. No more, "Wait until SP1 to upgrade." You have a higher level of comfort that the new features and versions are stable.

Any SQL Server horror stories? What's the biggest implementation misstep you've seen an organization make?
The mistakes I have seen in the past few years is trying the "lift-and-shift" approach to cloud migrations, only to see those workloads revert back to Earthed instances.

The reason for the migration failures are twofold. First, there is an expectation everything will "just work" the same as before. The second is the failure of admins to learn how to tune cloud workloads prior to migrating.

What's a relatively uncommon SQL Server problem that you've seen have disastrous consequences?
Most of the uncommon issues I have seen all involve the network. In one case, a network card on a client PC was old and the throughput was a fraction of newer cards. The user continued to complain there was a database issue and we did our best to track down the problem, but it took a while to discover the issue was a piece of hardware.

This scenario is repeated often, where someone blames the database, time is spent researching the issue, and hours/days/weeks later, the culprit is found to be hardware or a virtualization configuration setting.

What has been the most useful SQL Server feature addition or change in recent years?
There are too many to choose from. It is similar to asking me which child is my favorite. I'll go with the decoupling of SQL Server Management Studio (SSMS) from the install process. This allows for features to be rolled out to SSMS with more frequency than before. No need to wait for a new version of SQL Server to get new SSMS bits.

Are there any particular tools you recommend to DBAs to help them fix common problems?
Yes, I recommend any of the tools made by SolarWinds (Database Performance Analyzer, SQL Sentry, Database Performance Monitor) to help you find and fix common problems.

What's one often-overlooked thing about SQL Server troubleshooting that you wish more people knew about?
A database is a piece of software and it does what you tell it to do. For example, the engine does not get tired one day and suddenly the result is a bunch of deadlocks. So many times, people focus on the database engine as the root cause of their issues, when in fact the issue exists between the chair and the keyboard.  

The top common problems with SQL Server also apply to databases in general, and they serve as a good reminder when it comes to basic performance monitoring and troubleshooting.